Stabilizing arrangement for power boats



March 10, 1964 K. BRATEN 3,124,094

STABILIZING ARRANGEMENT FOR POWER BOATS Filed June 29, 1962 I 2Sheets-She et 1 FIG/a. FIG].

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March 10, 1964 K. BRATEN 3,124,094

STABILIZING ARRANGEMENT FOR POWER BOATS Filed June 29, 1962 2Sheets-Sheet 2 F/GZ.

IN vl/ z z z M United States Patent 3,124,094 STABILIZING ARRANGEMENTFOR POWER BGATS Kjell Britten, Kr. Anhertsvei 32, Rea, Norway Filed June29, 1962, Ser. No. 206,315 13 Claims. (Cl. 114-665) This inventionrelates to a stabilizing device for boats.

The main object of the invention is to provide a device which may beused for stabilizing a power boat.

In accordance with the invention the device comprises at least onestabilizing fin which is positioned in a sloping relation to the waterlevel surface and adapted to pivot about an axis substantially parallelto the longitudinal center axis of the ship.

In accordance with another feature of the invention the said sloping finis also pivotable about an axis extending transversely of the normaldirection of boat movement. The sloping fin has on its downwardlydirected face a longitudinal vertical fin or rib. Such a vertical finmay also be mounted on the upwardly directed face of the sloping fin.

In smaller boats the steering device is preferably mounted on the sternportion or the transom of the boat so that it is entirely located behindthe boat hull.

In greater boats the device may be positioned under the after portion ofthe vessel and the control and driving connections can be placed in asuitable well in the bottom of the ship. A stabilizing arrangementshould preferably comprise two stabilizing attachments, one on each sideof the longitudinal axis of the vessel.

From the above it appears that the sloping fin can be pivoted about twoaxes substantially crossing one another at a right angle, but notnecessarily lying in one and the same plane.

It is a disadvantage of small power boats that the stern end of the boathas a tendency to be pressed down into the water when the speed isincreased, particularly with a heavy load, or when the load is notdistributed correctly. A suitable adjustment of the sloping angle of thefins will cause the stern of the boat to be lifted from the water sothat the boat will be able to plane more easily. The stern end may alsobe lifted to some distance over the water surface. When the sloping finsare pivoted about the horizontal longitudinal axis in one or the otherdirection, the boat will move in an are without causing the side of thestern nearer the center of the arc to be pressed down into the water.This is advantageous, as a rather small boat may be used in a rough seaand yet move at a high travelling 'speed.

The above and other objects and advantages of the invention will be morefully appreciated from the following description when taken inconnection with the accompanying drawings, in which:

FIG. 1 is a vertical longitudinal section of a boat stern portion ortransom equipped with a stabilizing attachment of the invention,

FIG. 1a is a side view of a holding bracket for the fin liftingmechanism of the attachment of FIG. 1,

FIG. 2 is a rear elevational view of the stabilizing and steeringattachment, and

FIG. 3 shows the stern of the boat provided with a twin steeringarrangement of the invention.

Referring to FIG. 1, a support plate 3 of metallic or plastic materialis fixed by means of screws 2 on the transom 1 of a boat and a normallyhorizontal pivot 4 with its pivoting axis 4a extending in thelongitudinal direction of the boat is supported on the lower portion ofthe plate 3. A guiding plate 5 having a hub 6 is pivotally fixed on thepivot 4. The hub 6 engages the pivot 4. The hub is provided with agrease nipple 6a. The lower edge 7 of the plate 5 extends substantiallyhori- 3,124,094 Patented Mar. 10, 1964 "ice zontally, and the upperportion 8 of the plate 5 has a semi-circular guiding slot 9 for aguiding pin 10 one end of which is firmly threaded into the supportingplate 3.

The outer end of the pin 10 has threads carrying a nut 11. A helicalspring 12 pressing with one end against a washer 13 engaging the guidingplate 5 can be compressed more or less by means of the nut 11 and anintermediate washer 14 so that the friction force between the supportingplate 3 and the guiding plate 5 can be adjusted. The guiding plate 5carries an upwardly elongated lever arm 15 reinforced with a rib 15a,and the lever arm 15 has in its upper end a hole 16 for connection withthe steering wheel or handle of the boat.

As shown in FIGS. 1 and 2, the front edge of a plate shaped fin 18 ishingedly connected by a pin 17a with the lower edge 7 of the guidingplate 5. In the normal driving position the fin 18 is downwardly andrearwardly. The front of the fin 13 is about as wide as the guidingplate but the fin width increases gradually rearwardly. The pivotconnection can comprise one or more hinges 17. The fin 18 is pivotedabout the pin 17a for changing of the angle between the fin and thewater surface. If desired, the plate 13 may be lifted entirely from thewater, for instance when the boat shall be transported on a trailer orthe like. The underside of the fin 18 is provided with a longitudinalvertical fin 19 extending along the center line thereof.

Means for pivoting the fin 18 about the axis of the pin 17, comprise abracket Zil fixed on the upper portion of the lever arm 15 and havingtwo substantially horizontal arms 21 (FIG. In) each provided with ahorizontal slot 22. A sleeve 23 having a threaded bore carries twolateral bolts 24 guided in the slots 22 for movement against the actionof two helical springs 27 located between the sleeve walls and abutments29 arranged between the bracket arms 21. The springs are guided by pins28 fixed on the sleeve and extending through holes in the abutments 29.The lower end of a two-piece linking rod 33, 33a is hinged to a bracket25 on the fin 18, and the upper rod portion 33 is provided with threads26 cooperating with the threads in the bore of the sleeve 23. The top ofthe rod 33 is provided with a turning handle 27 by means of which theslope of the fin 18 may be adjusted. The lower portion 33a of theadjusting rod carries a connector 34 rotatably engaging the upperportion 33 of the rod.

When the boat travels straight forward or along a curve, it isstabilized by pivoting of the guiding plate 5 with the fin 18 about thehorizontal pivot 4 by means of the lever arm 15.

In a preferred embodiment of the invention two identical stabilizingattachments are located on opposite sides of the longitudinal centerplane of the boat.

The upper ends of the lever arms 15 are linked by means of a bar 30, asshown in FIG. 3. The bar 3 3 is made of two pieces so that its lengthcan be adjusted. The midportion of the bar has an eyelet 31 (FIG. 3) fora wire 32 or the like which is connected with the rudder tiller orsteering wheel. The bar 30' causes the two devices to carry outidentical pivoting motions about the axes 4a.

It should be understood that the invention is not limited to theembodiments shown in the drawings and described above as various changesmay of course be made without departing from the scope of the invention.

What I claim is:

l. A stabilizer attachment for a boat comprising, in combination:

(a) a support;

(12) attaching means for attaching said support. to a boat in apredetermined position;

() a plate shaped fin having two opposite major faces;

(d) pivot means interposed between said support and said fin for pivotalmovement of said fin about two axes toward and away from a normalposition in which the faces of said fin are directed upward and downwardrespectively, when said support is in said predetermined position, saidaxes being perpendicular to each other and normally horizontal; and

(e) means for pivoting said fin about one of said axes.

2. An attachment as set forth in claim 1, wherein said pivot meansinclude a pivot member pivotally secured to said support for movementabout the other one of said axes, said fin being pivotally atached tosaid pivot member for movement about said one axis.

3. An attachment as set forth in claim 2, wherein said other axisextends longitudinally of said boat when said support is attached tosaid boat by said attaching means in said predetermined position.

4. An attachment as set forth in claim 1, further comprising a ribmember on the normally downwardly directed face of said fin, said ribmember being elongated transversely of said one axis.

5. An attachment as set forth in claim 1, further comprising abutmentmeans for limiting pivotal movement of said fin about said other axis.

6. An attachment as set forth in claim 5, wherein said abutment meansinclude two abutment members, one abutment member being formed with anaperture and the other abutment member being arranged for movement insaid aperture, one of said abutment members being secured to saidsupport against movement about said other axis, and the other abutmentmember being connected to said fin for pivotal movement therewith aboutsaid other axis.

7. An attachment as set forth in claim 1, wherein said means forpivoting said fin include link means for connecting said fin to aportion of said boat upwardly spaced from said pivot means, said linkmeans having two portions threadedly engaged for varying the length ofsaid link means.

8. A stabilized boat comprising, in combination:

(a) a hull;

(b) a plate shaped fin having two opposite major faces;

(c) pivot means interposed between said hull and said fin for pivotalmovement of said fin about two normally horizontal axes perpendicular toeach other toward and away from a position in which the faces of saidfin are directed upward and downward respectively, one of said axesbeing transverse of the normal direction of movement of said boat; and

(d) pivoting means for pivoting said fin about said one axis.

9. A boat as set forth in claim 8, wherein said pivot means include apivot pin attached to said hull and having a normally horizontal axisextending in said normal direction of boat movement, a hub memberengaging said pivot pin for movement about the axis thereof, said finbeing hingedly secured to said hub member for movement relative theretoabout a normally horizontal axis transverse of said normal direction ofboat movement.

10. A boat as set forth in claim 9, further comprising cooperatingabutment means on said hull and on said hub member for limiting pivotalmovement of said hub memher about the axis of said pivot pin.

11. A boat as set forth in claim 10, wherein said abutment means includea guide plate on said hub member, said guide plate being formed with anaperture, and an abutment member fastened to said hull and engaging saidaperture.

12. A boat as set forth in claim 8, wherein said pivoting means includelink means interposed between said fin and a portion of said hullnormally upwardly spaced from said pivot means, said link meansincluding two link members threadedly connected for varying the lengthof said link means when said link members are rotated relative to eachother.

13. A stabilized boat comprising, in combination:

(a) a hull having a longitudinal axis;

(b) two plate shaped fins arranged on opposite sides of said axis, eachfin having two opposite major faces;

(c) pivot means interposed between said hull and each fin for pivotalmovement of said fin about two normally horizontal pivoting axesperpendicular to each other toward and away from a position in which thefaces of said fin are directed upward and down- Ward respectively, oneof said pivoting axes being transverse of said longitudinal axis; and

(d) pivoting means for pivoting each of said fins about one of saidpivoting axes thereof.

References Cited in the file of this patent UNITED STATES PATENTSFOREIGN PATENTS Great Britain of 1908 France July 6, 1925

1. A STABILIZER ATTACHMENT FOR A BOAT COMPRISING, IN COMBINATION: (A) ASUPPORT; (B) ATTACHING MEANS FOR ATTACHING SAID SUPPORT TO A BOAT IN APREDETERMINED POSITION; (C) A PLATE SHAPED FIN HAVING TWO OPPOSITE MAJORFACES; (D) PIVOT MEANS INTERPOSED BETWEEN SAID SUPPORT AND SAID FIN FORPIVOTAL MOVEMENT OF SAID FIN ABOUT TWO AXES TOWARD AND AWAY FROM ANORMAL POSITION IN WHICH THE FACES OF SAID FIN ARE DIRECTED UPWARD ANDDOWNWARD RESPECTIVELY, WHEN SAID SUPPORT IS IN SAID PREDETERMINEDPOSITION, SAID AXES BEING PERPENDICULAR TO EACH OTHER AND NORMALLYHORIZONTAL; AND (E) MEANS FOR PIVOTING SAID FIN ABOUT ONE OF SAID AXES.